Module

Kernel.lean

Nyll.SchemeTheory.RingTheory.Flat.Kernel
1 declaration indexed from sourceView source ↗

Module Flat ker of surjective of flat

Flatness of the kernel of a surjection between flat modules.

Declarations

Module.Flat.ker_of_surjective_of_flat
Source context 4 commands

Surrounding namespaces, section variables, and local commands at this declaration.

section ProofImplementation
namespace AlgebraicCurves.Foundations.Algebra.Proofs.Module_Flat_ker_of_surjective_of_flat
universe u
open TensorProduct
theorem _root_.Module.Flat.ker_of_surjective_of_flat
    {R : Type u} [CommRing R] {M P : Type u}
    [AddCommGroup M] [Module R M] [AddCommGroup P] [Module R P]
    [Module.Flat R M] [Module.Flat R P] (g : M →ₗ[R] P) (hg : Function.Surjective g) :
    Module.Flat R (LinearMap.ker g)